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1.
采用分步细乳液聚合法,合成了含氟有机硅细乳液。通过八甲基环四硅氧烷(D4)、四甲基四乙烯环四硅氧烷(Dv4)的阳离子开环聚合,先合成带乙烯基的有机硅聚合物,再自由基接枝含氟丙烯酸酯侧链。使用FTIR对聚合物的结构进行了表征,研究了Dv4单体和含氟丙烯酸酯单体(DFMA)的含量对乳液粒子的结构和乳液性能的影响。  相似文献   

2.
综述了含氟丙烯酸酯聚合物与疏水疏油作用相应的结构特点和改性机理,分析了含氟丙烯酸酯的合成技术及应用现状。研究结果表明:乳液聚合法是目前该类材料的主要合成方法,在使用较低含量氟单体的情况下达到聚合物较好的表面性能,制备性能优异、价格低廉、符合环保要求的水性含氟丙烯酸酯共聚物乳液,并扩大其应用市场成为目前研究的重点。  相似文献   

3.
水性含氟丙烯酸酯共聚物防水防油剂的研究   总被引:3,自引:0,他引:3  
李小瑞  辛华 《上海造纸》2005,36(3):49-52,61
含氟化合物具有优异的防水防油性能,水性含氟丙烯酸酯共聚物聚合速度快、对环境污染小,乳状液产品可直接应用与生产中、制备和使用成本相对低,因而得到了迅速发展.该文介绍了水性含氟丙烯酸酯共聚物的制备方法,水性含氟丙烯酸酯共聚物作为纸张防水防油剂的作用机理和应用,并总结了有关纸张防水防油性的测定方法.  相似文献   

4.
含氟化合物具有优异的防水防油性能,水性含氟丙烯酸酯共聚物聚合速度快、对环境污染小,乳状液产品可直接应用与生产中,制备和使用成本低,因而得到了迅速发展。本文介绍了水性舍氟丙烯酸酯共聚物的制备方法,水性舍氟丙烯酸酯共聚物作为纸张防水防油剂的作用机理和应用。并总结了有关纸张防水防油性的测定方法。  相似文献   

5.
采用不饱和的含氟单体与丙烯酸酯类单体在常压下反应合成核壳型含氟丙烯酸酯共聚物,并用其整理亚麻织物。采用傅里叶红外光谱仪、透射电子显微镜、X光电子能谱等分析手段研究了乳液及其胶膜的结构以及亚麻织物整理后应用性能的变化。结果表明:半连续种子乳液聚合法可合成出纳米级核壳结构的氟代丙烯酸酯共聚物乳液,用其整理亚麻织物,织物变得光滑平整。整理后的亚麻布样断裂强力明显提高,透湿透气性略有降低。胶膜对水和十六烷的接触角分别为98.32°和65.58°。  相似文献   

6.
含氟丙烯酸酯皮革防水剂的制备及性能研究   总被引:1,自引:0,他引:1  
以丙烯酸全氟辛基乙酯为主要单体,采用溶液聚合法制备了含氟丙烯酸酯皮革防水剂,采用红外光谱对聚合物进行了表征,研究了聚合方法、氟单体含量对聚合物性能的影响,分析了整理后皮革表面的防水防油性、耐洗性和柔软性,并进行了SEM分析。结果表明:用含氟丙烯酸酯共聚物整理后的皮革,具有良好的防水、防油和耐洗性,较好地保持了皮革的柔软性。  相似文献   

7.
以甲基丙烯酸六氟丁酯、丙烯酸乙酯、丙烯酸丁酯为主要原料,采用半连续乳液聚合法合成含氟丙烯酸酯共聚物乳液。研究表明:十一烯酸对乳液聚合稳定性有较大改善,随着氟单体含量的增加,聚合稳定性降低,乳胶膜的吸水率降低,接触角增加;当氟单体含量达到12%时,乳胶膜由亲水性转变为疏水性;氟单体的加入提高了革的动态防水性。  相似文献   

8.
以丙烯酸十二氟庚酯(G04),甲基丙烯酸甲酯(MMA),丙烯酸丁酯(BA)为主要单体,脂肪醇聚氧乙烯醚AEO-9和十二烷基苯磺酸钠(SDBS)为复配乳化剂,过硫酸铵(APS)为引发剂,制备含氟丙烯酸酯共聚物.探讨了n(BA)∶n(MMA)、引发剂的种类及用量、乳化剂种类及用量、反应温度、反应时间等因素对含氟丙烯酸酯共聚物性能的影响,并将自制的含氟丙烯酸酯聚合乳液对棉织物进行整理,结果表明:当n(BA)∶n(MMA)=3∶2,APS用量0.6%,乳化剂为m(SDBS)∶m(AEO-9)=3∶2,用量6%,温度为75℃,预乳液滴加时间为3.5h,后续反应时间为1 h时,所制备的含氟丙烯酸酯共聚物具有良好的防水透湿性能.  相似文献   

9.
含氟丙烯酸酯共聚物防水防油剂具有优良的防水、防油性,广泛用于纸张、皮革、织物等多种基材的整理。本文对国内外含氟丙烯酸酯共聚物防水防油剂领域的专利发展趋势、申请人分布进行了分析,并综述了含氟丙烯酸酯共聚物防水防油剂技术最新研发进程,以期为企业和科研机构的研发、创新活动以及开展知识产权战略提供参考。  相似文献   

10.
PU再生革胶乳的研究   总被引:2,自引:0,他引:2  
张洪涛  陈红 《皮革化工》1999,16(2):24-27
在四口烧瓶中,加入TDI、PPG、HOA、DBT,边通氮气边搅拌,逐步升温至80~85℃,反应3h,然后降温加入溶剂和中和剂,搅拌均匀后,加水乳化,蒸除溶剂后即得PU胶乳。该粘合剂用于制备再生革韧性高,耐弯曲,耐水性高。  相似文献   

11.
Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.  相似文献   

12.
An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.  相似文献   

13.
The characterization of the aromatic profile of several apricot cultivars with molecular tracers in order to obtain objective data concerning the aromatic quality of this fruit was undertaken using headspace–solid phase microextraction (HS–SPME). Six apricot cultivars were selected according to their organoleptic characteristics: Iranien, Orangered, Goldrich, Hargrand, Rouge du Roussillon and A4025. The aromatic intensity of these varieties measured by HS–SPME–Olfactometry were defined and classified according to the presence and the intensity of grassy, fruity and apricot like notes. In the six varieties, 23 common volatile compounds were identified by HS–SPME–GC–MS. Finally, 10 compounds, ethyl acetate, hexyl acetate, limonene, β-cyclocitral, γ-decalactone, 6-methyl-5-hepten-2-one, linalool, β-ionone, menthone and (E)-hexen-2-al were recognized by HS–SPME–GC–O as responsible of the aromatic notes involved in apricot aroma and considered as molecular tracers of apricot aromatic quality which could be utilized to discriminate apricot varieties.  相似文献   

14.
The advent of the functional barrier concept in food packaging has brought with it a requirement for fast tests of permeation through potential barrier materials. In such tests it would be convenient for both foodstuffs and materials below the functional barrier (sub-barrier materials) to be represented by standard simulants. By means of inverse gas chromatography, liquid paraffin spiked with appropriate permeants was considered as a potential simulant of sub-barrier materials based on polypropylene (PP) or similar polyolefins. Experiments were performed to characterize the kinetics of the permeation of low molecular weight model permeants (octene, toluene and isopropanol) from liquid paraffin, through a surrogate potential functional barrier (25 μm-thick oriented PP) into the food simulants olive oil and 3% (w/v) acetic acid. These permeation results were interpreted in terms of three permeation kinetic models regarding the solubility of a particular model permeant in the post-barrier medium (i.e. the food simulant). The results obtained justify the development and evaluation of liquid sub-barrier simulants that would allow flexible yet rigorous testing of new laminated multilayer packaging materials.  相似文献   

15.
Capillary electrophoresis (CE) and polarized light microscopy (PLM) were utilized in the detection of the adulteration of locust bean gum with guar gum. For CE analyses, standards of locust bean and guar gums were extracted with 30% CH3CN, removing the residual proteins from the gum matrix. A 8.75 mM NaH2PO4-20.6 mM Na2B4O7 buffer, pH 9, was used to separate these proteins and to identify marker proteins that were present in the guar gum. These markers did not co-migrate with components in the extracts of mechanically processed locust bean gum, and are used as indicators of adulteration. Using PLM with toluidine blue and iodine staining techniques, unadulterated locust bean gum samples were distinguished from mixed samples through the differential staining of components in locust bean versus guar and tara gums. These experiments in the use of CE and PLM provide orthogonal and complementary methods for the verification of 'true' positives and the elimination of 'false' positives.  相似文献   

16.
A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.  相似文献   

17.
An investigation is described in which various polyfunctional compounds were applied to wool in attempts to stabilize the temporary improvements in wrinkle-recovery brought about by ‘annealing’. Several reactive systems involving formaldehyde were found to produce the desired permanently improved wrinkle-recovery.  相似文献   

18.
19.
BADGE.2HCl and BFDGE.2HCl were determined in 28 samples of ready-to-drink canned coffee and 18 samples of canned vegetables (10 corn, 5 tomatoes and 3 others), all from the Japanese market. HPLC was used as the principal analytical method and GCMS for confirmation of relevant LC fractions. BADGE.2HCl was found to be present in one canned coffee and five samples of corn, BFDGE.2HCl in four samples of canned tomatoes and in one canned corn. No sample was found which exceeded the 1mg/kg limit of the EU for the BADGE chlorohydrins. However the highest concentration was found for the sum of BFDGE.2HCl and BFDGE.HCl.H2O at a level of 1.5mg/kg. A Beilstein test confirmed that all cans containing foods contaminated with BADGE.2HCl or BFDGE.2HCl had at lest one part coated with a PVC organosol.  相似文献   

20.
《造纸信息》2014,(8):79-79
Ministr y of Industr y and Information Technology confirmed that the main expected targets for energysaving and comprehensive utilization in 2014 are:energy consumption and CO2 emissions per unit of industrial added-value decreases by 4.5%,water consumption per ten thousand Yuan of industrial added-value decreases by7%,comprehensive utilization of industrial solid waste is further improved,and pollution emissions in key industries is markedly reduced.  相似文献   

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